R-Type Delta crappy emulation? (PSP)

[Sly Cherry Chunks]

So I downloaded this a couple of days ago to replace my now unusable PAL copy - I've played through it twice now and both times upon reaching the last stage, all the enemies were invisible - making the game unplayable. Anyone else having this problem?

[Thunder Force]

I seem to recall someone posting on the old forum, about similar problems with the last stage when running emulated on a PS2 with texture smoothing on (or something like that...)?

[Gydocker45]

With the latest official PSP firmware (6.00), R-Types and R-Type Delta don't run as smooth as they used to. The music skips and the graphics are very jerky and flicker a lot. Hopefully the next firmware will fix this problem.

[Specineff]

At the risk of invoking mod wrath, may I advocate for custom firmware? I'm still on 5.00, and Delta runs smoothly, ripped from an actual disc.

[Gydocker45]

At the risk of invoking mod wrath, may I advocate for custom firmware? I'm still on 5.00, and Delta runs smoothly, ripped from an actual disc.

Man... if there were an option to go back to the previous firmware, I would in this case.